A new foam-based method for the (bio)degradation of hydrocarbons in contaminated vadose zone.

An innovative foam-based method for Fenton reagents (FR) and bacteria delivery was assessed for the in situ remediation of a petroleum hydrocarbon-contaminated unsaturated zone. The surfactant foam was first injected, then reagent solutions were delivered and propagated through the network of foam lamellae with a piston-like effect. Bench-scale experiments demonstrated the feasibility of the various treatments with hydrocarbon (HC) removal efficiencies as high as 96 %. Compared to the direct injection of FR solutions, the foam-based method led to larger radii of influence and more isotropic reagents delivery, whereas it did not show any detrimental effect regarding HC oxidation. Despite 25 % of HCs were expelled from the treated zone because of high foam viscosity, average degradation rates were increased by 20 %. At field-scale, foam and reagent solutions injections in soil were tracked both using visual observation and differential electric resistivity tomography. The latter demonstrated the controlled delivery of the reactive solutions using the foam-based method. Even if the foam-based method duration is about 5-times longer than the direct injection of amendment solutions, it provides important benefits, such as the confinement of harmful volatile hydrocarbons during Fenton treatments, the enhanced reagents delivery and the 30 % lower consumption of the latter.

Grasping convergent evolution in syngnathids: a unique tale of tails.

Seahorses and pipehorses both possess a prehensile tail, a unique characteristic among teleost fishes, allowing them to grasp and hold onto substrates such as sea grasses. Although studies have focused on tail grasping, the pattern of evolutionary transformations that made this possible is poorly understood. Recent phylogenetic studies show that the prehensile tail evolved independently in different syngnathid lineages, including seahorses, Haliichthys taeniophorus and several types of so-called pipehorses. This study explores the pattern that characterizes this convergent evolution towards a prehensile tail, by comparing the caudal musculoskeletal organization, as well as passive bending capacities in pipefish (representing the ancestral state), pipehorse, seahorse and H. taeniophorus. To study the complex musculoskeletal morphology, histological sectioning, µCT-scanning and phase contrast synchrotron scanning were combined with virtual 3D-reconstructions. Results suggest that the independent evolution towards tail grasping in syngnathids reflects at least two quite different strategies in which the ancestral condition of a heavy plated and rigid system became modified into a highly flexible one. Intermediate skeletal morphologies (between the ancestral condition and seahorses) could be found in the pygmy pipehorses and H. taeniophorus, which are phylogenetically closely affiliated with seahorses. This study suggests that the characteristic parallel myoseptal organization as already described in seahorse (compared with a conical organization in pipefish and pipehorse) may not be a necessity for grasping, but represents an apomorphy for seahorses, as this pattern is not found in other syngnathid species possessing a prehensile tail. One could suggest that the functionality of grasping evolved before the specialized, parallel myoseptal organization seen in seahorses. However, as the grasping system in pipehorses is a totally different one, this cannot be concluded from this study.

EDART, a discrete algebraic reconstructing technique for experimental data obtained with high resolution computed tomography.

A novel reconstruction method is presented to improve the image quality of three dimensional (3D) datasets for samples consisting of only one material and surrounding air, obtained with high resolution X-ray Computed Tomography (µCT). It combines discrete tomography with iterative reconstruction algorithms, it is applicable for routine µCT applications and is referred to as the Experimental Discrete Algebraic Reconstruction Technique (EDART). A fast and intuitive method to estimate the attenuation coefficient and segmentation threshold, in case these are unknown, is included. Experimental results illustrate that EDART allows the improvement of the reconstruction quality as compared to standard iterative reconstruction when few projections are available, without significantly increasing the reconstruction time.

Electromagnetic stimulation to optimize the bone regeneration capacity of gelatin-based cryogels.

One of the key challenges in reconstructive bone surgery is to provide living constructs that possess the ability to integrate in the surrounding host tissue. Bone graft substitutes and biomaterials have already been widely used to heal critical-size bone defects due to trauma, tumor resection and tissue degeneration. In the present study, gelatin-based cryogels have been seeded with human SAOS-2 osteoblasts followed by the in vitro culture of the cells. In order to overcome the drawbacks associated with static culture systems, including limited diffusion and in homogeneous cell-matrix distribution, the present work describes the application of a bioreactor to physically enhance the cell culture in vitro using an electromagnetic stimulus. The results indicate that the physical stimulation of cell-seeded gelatin-based cryogels upregulates the bone matrix production. We anticipate that the scaffolds developed consisting of human bone proteins and cells could be applied for clinical purposes related to bone repair.

A LabVIEW® based generic CT scanner control software platform.

UGCT, the Centre for X-ray tomography at Ghent University (Belgium) does research on X-ray tomography and its applications. This includes the development and construction of state-of-the-art CT scanners for scientific research. Because these scanners are built for very different purposes they differ considerably in their physical implementations. However, they all share common principle functionality. In this context a generic software platform was developed using LabVIEW® in order to provide the same interface and functionality on all scanners. This article describes the concept and features of this software, and its potential for tomography in a research setting. The core concept is to rigorously separate the abstract operation of a CT scanner from its actual physical configuration. This separation is achieved by implementing a sender-listener architecture. The advantages are that the resulting software platform is generic, scalable, highly efficient, easy to develop and to extend, and that it can be deployed on future scanners with minimal effort.

[Systemic lupus erythematosus over hemophagocytic lymphohistiocytosis]. / Systemische lupus erythematosus-geassocieerde hemofagocytaire lymfohistiocytose.

A woman was admitted to the hospital with lymphadenopathy, fever and a generalised exanthema. Laboratory examination revealed leucopenia, anaemia, high sedimentation, elevated CRP and a markedly elevated serum ferritin. Further exploration showed a positive anti-nuclear factor-titre with anti-double-stranded DNA antibodies, positive p-ANCA and a falsely positive syphilis-test. Bone marrow examination revealed an elevated number of phagocytizing macrophages. Diagnosis of secondary haemophagocytic lymphohistiocytosis in a patient with systemic lupus erythematosus was made, a serious and sometimes fatal condition with often repeated exacerbations of the systemic lupus erythematosus that stays active for long periods in spite of the use of immunosuppressive therapy. Haemophagocytic lymphohistiocytosis and systemic lupus erythematosus are sometimes difficult to differentiate because the clinical presentation and laboratory findings are frequently very similar. The diagnosis depends on the clinical picture, blood and bone marrow examination. Bone marrow reveals an elevated haemophagocytosis. In patients with secondary haemophagocytic lymphohistiocytosis, the treatment of the underlying disorder is sometimes sufficient. In some cases there is need for a specific treatment with corticosteroids, intravenous immunoglobulin, immunosuppressive therapy or etoposide.

Virtual histology by means of high-resolution X-ray CT.

Micro-CT is a non-destructive technique for 3D tomographic investigation of an object. A 3D representation of the internal structure is calculated based on a series of X-ray radiographs taken from different angles. The spatial resolution of current laboratory-used micro-CT systems has come down over the last years from a few tens of microns to a few microns. This opens the possibility to perform histological investigations in 3D on a virtual representation of a sample, referred to as virtual 3D histology. The advantage of micro-CT based virtual histology is the immediate and automated 3D visualization of the sample without prior slicing, sample preparation like decalcification, photographing and aligning. This not only permits a drastic reduction in preparation time but also offers the possibility to easily investigate objects that are difficult to slice. This article presents results that were obtained on punch biopsies of horse skin, (dental) alveolus of ponies and chondro-osseous samples from the tarsus of foals studied with the new high resolution micro-CT set-up (HRXCT) at the Ghent University (Belgium) (http://www.ugct.ugent.be). This state-of-the-art set-up provides a 1 micron resolution and is therefore ideally suited for a direct comparison with standard light microscopy-based histology.

Chemical and morphological changes of historical lead objects as a result of the use of electrolytic reduction as a stabilization treatment.

This paper focuses on the evaluation of the treatment related to chemical and morphological changes of corroded lead artifacts when using electrolytic reduction as a stabilization method. Synchrotron radiation X-ray diffraction and X-ray photoelectron spectroscopy were used to study the chemical changes of the corrosion layer and on the top nanometer of surface, respectively. Neutron tomography and scanning electron microscopy were used to visualize potential morphological changes on millimeter and micrometer level, respectively. The results of this study have shown that electrolytic reduction is a reliable way to stabilize and conserve active corroded lead artifacts. The corrosion products are actually converted into metallic lead, while the morphological changes due to the treatment are limited.

Electroconvulsive therapy in Belgium: a nationwide survey on the practice of electroconvulsive therapy.

OBJECTIVE: To review and describe the practice of electroconvulsive therapy (ECT) in Belgium. METHODS: A 30-item questionnaire on the practice of ECT was sent to all institutions providing ECT. RESULTS: In 2003 ECT was offered in 32 hospitals. Although ECT hospitals are equally spread over three regions, there is a significant difference in the ECT utilization rate. There are no major regional differences in the practice of ECT. Fifty-three percent of the hospitals reported less than 10 treatment sessions per month. The major indication for ECT was depression (89.7%). Propofol was the anesthetic most commonly used (75%). Eleven departments (34.3%) used a sine wave device. Bitemporal electrode placement was the preferred option in 65.6% of all departments, and 37% of these used the combination of bitemporal electrode placement and a fixed high stimulus dose. Continuation ECT and outpatient ECT were rarely used. LIMITATIONS: This questionnaire study relies upon answers given by psychiatrists, and did not audit actual practices. CONCLUSIONS: Although ECT is widely available in Belgium, it remains underused and the practice of ECT is amenable for improvement. Guidelines should be implemented and continuing education is needed.

High prevalence of mental disorders in primary care.

OBJECTIVE: To determine the prevalence of common mental disorders in an adult primary care population. DESIGN: Cross-sectional survey in randomly selected subjects, using the PRIME-MD questionnaire. SETTING: Eighty-six general practices in Belgium. SUBJECTS: A total of 2316 randomly selected patients, aged 18 years or older and consulting their general practitioner for other than administrative reasons alone, with slightly more women (58.1%) than men (41.3%). MAIN OUTCOME RESULT: Prevalence rates of mental disorders most commonly seen in primary care practice (mood, anxiety, somatoform, eating and alcohol disorders). METHODS: To facilitate data collection and processing, the entire PRIME-MD questionnaire was programmed on a handheld computer. Patient answers and physician assessments were immediately electronically recorded during the interview. All investigators were trained on the use of the PRIME-MD. The recruitment period lasted 6 weeks: from 15 February to 25 March 1999, and patients were randomly selected for the interview based on a computerized procedure. RESULTS: Although only 5.4% of all patients consulted for a psychiatric reason, a threshold/subthreshold psychiatric disorder was detected in 42.5% of all patients. Most commonly detected disorders were mood disorders in 31.0% (major depressive disorder, 13.9% and dysthymia, 12.6%), anxiety disorders in 19.0% (generalized anxiety disorder, 10.3%), somatoform disorders in 18.0% and probable alcohol abuse/dependence in 10.1%. The results also showed the important rate of comorbidity between these disorders. CONCLUSION: The present study confirms the high prevalence of mental disorders in a general practice setting, and their frequent association. Prevalence rates of our study are even higher than those obtained in previously conducted trials. Our study also demonstrates the utility of the PRIME-MD as a screening tool for mental disorders in primary care. In addition the use of the handheld computer software version of the PRIME-MD allowed us to screen for mental disorders in patients who are unable to attend the GP office and are seen during 'home' visits.

A review of the efficacy and tolerability of venlafaxine.

Venlafaxine is a selective serotonin norepinephrine reuptake inhibitor with no activity at muscarinic, histaminergic or adrenergic receptors. The antidepressant activity of venlafaxine has been demonstrated in placebo-controlled and active comparator-controlled clinical trials. Venlafaxine was effective in outpatients and hospitalized patients with major depression and in those with melancholia, agitated or retarded symptoms, and refractory or treatment-resistant depression. Venlafaxine was at least as effective as comparative antidepressants and was more effective than fluoxetine or imipramine in some trials. A positive dose-response relationship has been shown with venlafaxine. When doses of venlafaxine are titrated rapidly upward, an onset of antidepressant action has been detected within one week in some studies. Venlafaxine is well tolerated during short- and long-term treatment. The most common adverse effects are nausea, somnolence and dry mouth. The overall tolerability of venlafaxine appears to exceed that of tricyclic antidepressants and compares favorably with that of selective serotonin reuptake inhibitors. Venlafaxine is a novel antidepressant that is appropriate for first-line therapy in patients with major depression.

An open-label evaluation of the long-term safety of oral venlafaxine in depressed elderly patients.

This open-label, multicenter study of depressed men and women > or = 65 years old was conducted at 18 European hospitals to evaluate the safety, efficacy, and clinical acceptability of venlafaxine in elderly depressed patients during 1 year. Patients received venlafaxine orally as 25-mg tablets two or three times daily for up to 12 months, Dosages were titrated upward during the first 15 days and then maintained between 50 and 150 mg/day. Safety was assessed on the basis of study events, vital signs, electrocardiograms tracings, and laboratory determinations. Efficacy was assessed using the Montgomery-Asberg Depression Rating Scale (MADRS), the Clinical Global Impressions (CGI) scale, and the Hospital Anxiety and Depression scale. Patients' subjective ratings of the drug's tolerability and efficacy were collected. Study events were reported by 62% of patients. Few clinically or statistically significant changes occurred in vital signs or electrocardiogram or laboratory findings. No serious study events, including three deaths, were considered unexpected given the nature of the population and the length of treatment. Most patients (81%) believed they had no side effects. Clinical response was achieved in 67% of patients by month 2 (as measured by improvement on the CGI) and by 64% of patients by month 3 (as measured by improvement on the MADRS), suggesting that venlafaxine demonstrates antidepressant efficacy. Eighty-five (73%) patients were still in the study after 6 months and 77 (66%) were still participating at 12 months. Overall, most patients (80%) felt much or very much improved at the end of the study. Venlafaxine was safe, effective, and clinically acceptable treatment for depression in elderly patients.

A double-blind comparison of venlafaxine and fluoxetine for treatment of major depression in outpatients.

1. This was a randomized, double-blind comparison of the efficacy and safety of venlafaxine and fluoxetine in outpatients with major depression. 2. Three hundred fourteen patients were randomly assigned to either venlafaxine 37.5 mg twice daily or fluoxetine 20 mg once daily for a maximum of 8 weeks. 3. If the response was inadequate after two weeks of treatment, the dosage of venlafaxine could be increased to 75 mg twice daily. 4. A clinical response, defined as at least a 50% decrease from baseline in the total HAM-D score, was attained at week 6 in 72% of patients on venlafaxine and 60% of patients on fluoxetine (p = 0.023). 5. Among patients who increased their dose at 2 weeks, venlafaxine was significantly (p < 0.05) superior from week 3 onward on the HAM-D. 6. Venlafaxine 75 mg daily is comparable to fluoxetine, but at 150 mg daily, it may be superior to fluoxetine in outpatients with major depression who do not respond early to treatment.

Mirtazapine is more effective than trazodone: a double-blind controlled study in hospitalized patients with major depression.

Two hundred hospitalized patients with DSM-III diagnosis of moderate to severe major depressive episode were randomized to receive mirtazapine or trazodone for 6 weeks in a double-blind trial. The dosages were 24-72 mg/day for mirtazapine and 150-450 mg/day for trazodone. The improvement on all depression rating scales used was generally greater for mirtazapine, with statistically significant differences over trazodone in the Hamilton Psychiatric Rating Scale for Depression total score and two subscores (the Bech melancholia factor and retardation factor), the Brief Psychiatric Rating Scale total score, the General Psychiatric Impression Global Assessment Scale, the Beck score and responder rates. Mirtazapine was well tolerated, while the trazodone-treated patients experienced somnolence more frequently, particularly during the first 2 weeks of treatment. Furthermore, postural symptoms were a clinical problem in 6% of the trazodone-treated patients. In this trial, mirtazapine showed significant clinical advantages over trazodone in terms of overall efficacy and tolerability.

Controlled comparison of nefazodone and amitriptyline in major depressive inpatients.

Nefazodone, a phenylpiperazine antidepressant, exhibits novel dual activity on serotonin (5-HT) neurons; it binds to 5-HT2 receptors and inhibits 5-HT reuptake. Flexible doses of nefazodone (100-400 mg/day) and amitriptyline (50-200 mg/day) were compared in 106 major depressive inpatients in a 6-week double-blind study. Results showed significant superiority of amitriptyline over nefazodone on all rating instruments: Montgomery and Asberg depression rating scale (P < 0.0001), Hamilton depression scale (P < 0.0006), Clinical Global Impressions (P < 0.0001) and Patient Global Assessment (P < 0.01). A total of 65% of patients under amitriptyline and 56% of patients under nefazodone reported adverse events during the study, with significantly more dry mouth in the amitriptyline group (39% versus 11%, P = 0.001). Modal daily doses within the last treatment week reached 242 mg with nefazodone and 124 mg with amitriptyline. The lower efficacy of nefazodone, which contradicts comparative trials with imipramine in US patients, is discussed with regard to the dose of nefazodone, probably below the optimal therapeutic range for melancholic patients, and to the clinical differences between the patient samples.

An open multicentre study to evaluate the efficacy and tolerance of fluoxetine 20 mg in depressed ambulatory patients.

In this study, 544 out-patients suffering from depressive disorders were enrolled in 6 weeks open study with fluoxetine 20 mg. A statistically significant decrease of the Hamilton Rating Scale for Depression (HRS-D) score is observed during treatment. All individual item HRS-D scores and in particular suicidal ideation, sleep disturbances and anxiety showed the same improvement. Side-effects were carefully recorded and presented a lower incidence rate than in other studies. New issues in methodology management concerning ambulatory studies are discussed.

Moclobemide versus clomipramine in the treatment of depression: a double-blind multicentre study in Belgium.

Moclobemide and clomipramine were compared for efficacy, tolerance and safety in 63 mixed endogenous and nonendogenous depressed patients. Treatment was given for at least 4 weeks in a double-blind, randomized, parallel-group design. The mean Hamilton Rating Scale for Depression score decreased gradually during treatment with no differences between groups. Two patients on clomipramine and none on moclobemide were withdrawn for lack of efficacy, and poor tolerance caused 3 patients on moclobemide and 7 on clomipramine to stop treatment prematurely. Patients with endogenous depression responded better to clomipramine, whereas nonendogenous disorders did better on moclobemide. Adverse events were more frequent in the clomipramine group and more of these were severe or very severe than for moclobemide. Thus, although no significant difference in efficacy was seen, moclobemide appeared to be tolerated better than clomipramine. The numbers were small, however, and many patients received concomitant medication, and the results are therefore difficult to interpret.

Treatment of depressive anxiety states associated with psychosomatic symptoms. A double-blind multicentre clinical study: mianserin versus melitracen-flupentixol.

A four-week randomized multicentre study comparing mianserin and melitracen-flupentixol was conducted in 90 outpatients suffering from depressive anxiety states with a predominantly psychosomatic symptomatology. Both patient groups showed a favourable clinical response to treatment as well as a good tolerance. No significant differences were observed in the drop-out rates or in the incidence of side-effects, although drowsiness tended to develop more frequently during the first days of mianserin treatment. The improvement scores of the groups showed that mianserin has significant advantages when depressed mood, sleep disturbances and autonomic disregulations predominate the depressive anxiety state.

The influence of prostaglandin E2 on the electroencephalogram of normal subjects and epileptic patients.

In 1973 R.C. Lyneham and others warned against the possible epileptogenic effect of prostaglandins. We studied the influence of this substance on the electroencephalogram of 53 subject (31 non-epileptics and 22 epileptics) before and during the administration of PG E2. Forty-eight tracings remained unchanged, four showed a slight improvement and one showed some worsening during infusion of PG E2. One patient, suffering from daily psychomotor attacks had, accidentally a fit during the trial. It can be concluded that PG E2 does not alter the electroencephalogram in a significant way and that it does not induce epileptic seizures.